Our current electric grid can't support mass scale electric vehicle use . Recharge stations are not independent from the current grid . We litteraly need to rebuild the ENTIRE grid . That's a huge footprint . Lets just look at how much of an effect building our current infrastructure took and multiply that many times over since the new electric grid must be significantly better . This is assuming ICE cars are still in the 30-20% range . The current solution ( which you are alluding to ) is having charging stations independent from the grid that can rapidly charge a car . Logistically cars would have to recharge more often than ICE cars AND at a similar rate per mile . I can get 400 mile range in 3 mins at any pump . I think a tesla can rapid charge in like 15 mins right ? Do the math ..Taken in isolation yes, but it has to be balanced against the reduction in footprint of the ICE powered vehicles it replaces.
Even taking into account the environmental impact of generating the energy to power an EV, they are still significantly less of an impact that ICE's, by up to 50 times less CO2 produced per km, as they are significantly better in terms of power efficiency than ICEs. As electric generation moves to lower impact models that difference will only increase, and ICE's have almost zero hope of even keeping pace.
In the West as far as re-fueling infrastructure goes it has a lot lower initial footprint that many suspect, particularly given the advances in recharging speeds and efficiencies, not to mention that EV's (particularly for commercial) allow for battery swaps.
As such I would not agree that we would be looking at clsoe to 100+ years to see benefit from this at all.